Josephson vortices play an essential role in superconducting quantum electronics devices. Often seen as purely conceptual topological objects, 2 π -phase singularities, their observation and manipulation are challenging. Here we show that in Superconductor—Normal metal—Superconductor lateral junctions Josephson vortices have a peculiar magnetic fingerprint that we reveal in Magnetic Force Microscopy (MFM) experiments. Based on this discovery, we demonstrate the possibility of the Josephson vortex generation and manipulation by the magnetic tip of a MFM, thus paving a way for the remote inspection and control of individual nano-components of superconducting quantum circuits.

Adding ferromagnetism to superconductor leads to spatially patterned phases of spontaneously generated vortex-antivortex pairs.

We report a study of the relaxation time of the restoration of the resistive superconducting state in single crystalline boron-doped diamond using amplitude-modulated absorption of (sub-)THz radiation (AMAR). The films grown on an insulating diamond substrate have a low carrier density of about 2.5 × 10 21 cm −3 and a critical temperature of about 2 K. By changing the modulation frequency we find a high-frequency rolloff which we associate with the characteristic time of energy relaxation between the electron and the phonon systems or the relaxation time for nonequilibrium superconductivity. Our main result is that the electron-phonon scattering time varies clearly as T −2 , over the accessible temperature range of 1.7 to 2.2 K. In addition, we find, upon approaching the critical temperature T c , evidence for an increasing relaxation time on both sides of T c .

We have developed planar nanoSQUID with nanobridge-type Josephson junctions based on the oxidation resistant and high H c2 MoRe alloy. The objective of the research was to reduce size of the SQUID loop with the aim being to reduce magnetic flux noise and improve the spatial resolution of the SQUID sensors. Employing RF-magnetron sputtering, electron-beam lithography, and reactive ion etching in CHF 3 + O 2 plasma using Al hard masks, we have realized nanoSQUIDs with Josephson junctions in the form of 30 − 50 nm wide nanobridges and an effective magnetic flux capture radius of ~95 nm. The critical temperature of the fabricated devices was T c = 7.9 K. The I(V)-characteristics demonstrated critical current I 0 ≃ 114 µA at 4.2 K and modulation period in magnetic fields of ~700 Oe.